Background: Anterior cruciate ligament reconstruction (ACLr) often leads to asymmetries between limbs, with variable return-to-performance rates in athletes. The single-leg countermovement jump (SLCMJ) is commonly used to assess postoperative knee function. However, limited research has explored deficits specifically during the unweighting phase of the jump. Methods: This study assessed 53 recreational athletes (11 females, 42 males) between 6 and 9 months post-ACLr using a dual force plate system (1000 Hz). Each participant performed three maximal-effort SLCMJs per limb. Outcome measures included jump height, negative peak velocity, minimum force, and center of mass (COM) displacement. Paired t-tests and Wilcoxon tests were used to compare the ACLr limb with the contralateral limb. Results: Compared to the healthy limb, the ACLr limb showed significantly lower negative peak velocity (−0.80 ± 0.40 m/s vs. −0.94 ± 0.40 m/s, p < 0.001), higher minimum force (36.75 ± 17.88 kg vs. 32.05 ± 17.25 kg, p < 0.001), and reduced COM displacement (−17.62 ± 6.25 cm vs. −19.73 ± 5.34 cm, p = 0.014). Eccentric phase duration did not differ significantly. Conclusions: Athletes post-ACLr demonstrate altered neuromuscular control during the early SLCMJ phase. These findings highlight the importance of rehabilitation strategies targeting eccentric strength and symmetry restoration.

Background: Conventional rehabilitation after anterior cruciate ligament reconstruction often follows a rigid, phase-based model. This structure may overlook individual differences in healing, neuromuscular control, and psychological readiness, leading to low return-to-sport rates and a high risk of reinjury. Methods: This narrative review proposes a flexible rehabilitation framework based on overlapping progression blocks. Inspired by principles of strength and conditioning, motor learning, and cognitive training, this model emphasizes continuous, individualized development instead of fixed timelines. Results: The proposed model integrates essential components—such as joint mobility, muscle activation, motor control, and psychological factors—throughout the entire recovery process. Functional testing is redefined as a dynamic and ongoing diagnostic tool that helps clinicians identify areas needing further development, rather than acting as a simple pass/fail gateway. Progression is guided by demonstrated readiness rather than time or phase completion. Conclusions: Rehabilitation using adaptive, overlapping progression blocks offers a more holistic and responsive approach. It allows for better personalization, supports safer decision-making, and improves the transition back to sport through sustained development of physical and cognitive capacities.